Re: [ANNOUNCE][CFT] kexec for v2.5.48 && kexec-tools-1.7 -- Success Story!

Eric W. Biederman
2002-11-19T10:18:50Z

Andy Pfiffer <andyp@osdl.org> writes:

> On Mon, 2002-11-18 at 00:53, Eric W. Biederman wrote:
> > kexec is a set of systems call that allows you to load another kernel
> > from the currently executing Linux kernel. The current implementation
> > has only been tested, and had the kinks worked out on x86, but the
> > generic code should work on any architecture.
>
> Great News, Eric. For the first time *ever* I got a kexec reboot to
> work on my most troublesome machine (see below).

Cool. I was pretty certain it would get into Linux but the fact the device
drivers are not hanging up is a real plus.

> Current .config settings:
> # CONFIG_SMP is not set
> CONFIG_X86_GOOD_APIC=y
> # CONFIG_X86_UP_APIC is not set
> CONFIG_KEXEC=y
>
> Oddly, kexec_test still hangs.
> # ./kexec-1.7 --force ./kexec_test-1.7
[snip...]
> <hang>

Yep. I really haven't tracked and fixed the cause of the hang,
I just avoided the issue entirely. Eventually I will come back
and look into what it takes to improve the odds of having BIOS calls,
work. --real-mode restores the old kexec behavior.

All of the real changes were to the user space code. The kernel
patch stayed the same.

> Complete kernel boot-up log attached below. I'm going to try to find my
> other 576MB of RAM with the right command-line magic... ;^)

Or you can write a routine to gather that information dynamically and send
me a patch for /sbin/kexec. Though it may take another proc file to do
that one properly.

Eric